The 'Daisyworld' model of Ecologist James Lovelock, first published in
1983, is a simple model of planetary self-regulation, bi-stability and
homeostasis. It is considered a 'parable' of planetary self-regulation,
achieved via feedback between life and its environment. The original model
had a simple gray plant, populated by two species of daisy: one black and
one white. The number and proportion of the daisy species alter their local
temperature in opposite directions (a white daisy reflects solar radiation,
a black one absorbs it). The Daisyworld model demonstrated a global regulation
of planet surface temperature in response to changes in the amount of solar
radiation falling on the planet. This is achieved by a feedback loop between
planetary albedo and daisy growth rates.

In 1998, a paper by Robertson and Robinson argued that if there were variation
of optimum growth temperature within the daisy population, then the population
should adapt towards the prevailing conditions. Robertson and Robinson showed
that high rates of adaptation destroyed temperature regulation in Daisyworld.
Lenton and Lovelock responded in a 2001 paper, claiming that with bounds
on the range of adaptation, regulation was maintained. However, their model
showed wide variation for different runs, with the mean of 10 separate runs
showing only 'minor temperature regulation'.

In this project you will develop an evolutionary Daisyworld model in order
to test the effects of adaptation on self-regulation. The goal is to better
understand the effects of mutation rate and adaptive bounds on this model.

The 2006/2007 summer cricket season was imbued with controversy as Cricket
Australia banned the 'Mexican wave' across stadiums in Australia. Many
fans reacted angrily, defying the new laws, potentially facing eviction
from the ground and heavy fines. A campaign to 'save the wave' was quickly
begin, with commentators saying the ban had gone too far, ruining people's
enjoyment of the game, and participation as spectators.

The rational given to banning the Mexican wave is that, when throwing
their arms in the air, some people choose to throw objects that fall on
the people below, potentially risking serious injury.

For this project you will develop an agent-based model of crowd behaviour,
designed to test theories about the initiation and propagation of the Mexican
wave in stadium crowds. You will need to model agents (representing the
people in the stadium) as well as the physical layout of the stadium itself.

Some questions to be asked of the model:

How many people does it take to initiate a wave, i.e. what is the 'critical
mass' of people wanting to start a wave necessary to ensure it continues
into a stadium-wide phenomena? (The current strategy for policing the wave
is to remove selected individuals who initiate the wave, so the model can
put this strategy to the test).

How does the size, capacity and occupancy of the stadium influence the
initiation and propagation of the wave?

Would a banning of throwing objects be a better strategy for public safety
than banning the wave outright?

The so-called 'superformula' is generic geometric transformation developed
by the engineer Johan Gielis. It is based on the idea that relatively simple
parameterised formula can represent a wide variety of geometric shapes.
For example, the circle, square, and ellipse are all members of the set
|x/a|^n + |y/b|^n = 1. The superformula can represent a large number of
natural profiles, particularly those found in plants. The original formulation
was confined to two-dimensional space. The aim of this project is to develop
a three-dimensional modelling system based on the use of the superformula.
Some possibilities include the use of generalised cylinders (using superformula
representations for profile and carrier curves), or implicit surface representations.
The system developed should be applied to practical modelling of a variety
of organic shapes.

For this project you will need to have successfully completed CSE3313
Computer Graphics. Knowledge of OpenGL and a hunger for mathematical visualisation
would also be helpful.

The role of group selection is somewhat controversial amongst evolutionary
biologists. Group selection refers to the "process of genetic change
brought about or maintained by the differential extinction and/or proliferation
of populations" (Wade 1976, 1977). The aim of this project is to construct
a computer simulation and visualisation of a set of populations of software
agents, each with its own inter-agent and agent-environment interactions.
This set of ecosystem simulations will be used to explore the potential for
ecosystem replication and evolution. That is, the project investigates the
evolutionary process as it applies to *groups* of agents, rather than the
usual scenario in which evolution acts upon individual organisms in a population.

Important questions that will be addressed by the student include:
What are the necessary and sufficient conditions for the evolution of virtual
ecosystems?
How does group selection compare against individual selection under different
circumstances?

New computer graphics visualisation tools will need to be developed
in order to interpret the results of the simulations conducted during
the course of the project. Students will require a sound programming
knowledge (C/C++ preferred, CSE2305, CSE3308) and experience with computer
graphics programming (OpenGL, CSE3313) and multimedia (CSE2325/3325).

References:

Wade, M.J. 1976. Group selection among laboratory populations of Tribolium.
Proceedings of the National Academy of Sciences U.S.A. 73: 4604—4607